High avalanche risk in Sea to Sky backcountry alpine

The risk also high in Whistler backcountry alpine with heavy snow in the forecast

AVALANCHE AWARE Forecasters recommend against travel in the alpine backcountry due to the current high risk of avalanches above the treeline.

Thanks to forecasted heavy snow this weekend, the Canadian Avalanche Centre (CAC) has issued a “High” avalanche warning for the entire Sea to Sky avalanche zone up until Sunday, when the danger rating in the alpine is expected to drop to "Considerable."

According to the avalanche prediction centre, travel in avalanche terrain at alpine elevations is not recommended due to very dangerous avalanche conditions. There is danger at the treeline so careful snowpack evaluation, cautious route finding and conservative decision making is required for any backcountry travel. The avalanche risk at the treeline is rated as considerable. Below the treeline the risk is rated as moderate.

The Whistler Blackcomb Avalanche Advisory aligns with the CAC information.

According to the WB Advisory: "Skier triggered storm snow slabs are likely from steep lee start zones. Natural or skier triggered deep slabs stepping down to the November 5th crust are possible from steep smooth alpine features and isolated rocky terrain."

WB has reported that an avalanche was triggered by a skier last Saturday and through the controlled use of explosives large Isolated avalanches were triggered earlier this week.

Anyone who does venture into the backcountry is reminded to watch for winch-cats or snowmobile traffic when re-entering the ski and snowboard area after the WB operating hours.

Reported Thursday, Nov. 29:

Whistler Blackcomb issued a backcountry advisory for Whistler backcountry that states alpine and treeline areas beyond the Ski Area Boundary were Moderate on Thursday, Nov. 29; with the advisory rising to Considerable in the alpine and staying Moderate in the treeline for Friday, Nov. 30.

On Saturday, Dec. 1, the advisory rises to High for Whistler backcountry alpine and Considerable for the backcountry treeline.

For all three days the rating is “below threshold” or Moderate below the treeline level in the Whistler backcountry.

While the alpine avalanche risk in the Sea to Sky region outside Whistler is High for both Friday and Saturday, it remains Considerable for both days in the treeline, and Moderate below the treeline.

“Heavy amounts of new snow will build storm slabs on all aspects, overlying a variety of weak surface layers. Storm slabs, and new wind slabs will be touchy, and widespread natural avalanche activity is likely with heavy loading from snow and wind,” the bulletin from the Canadian Avalanche Centre said.

The region is forecasted to receive a dump of up to 80 centimetres of snow in the alpine by Saturday, according to Environment Canada.

This is the first time this season that a High avalanche warning has been announced this winter season.

High conditions mean very dangerous avalanche conditions. Travel in avalanche terrain is not recommended.